02/2014
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First example:
1. Fault: measure loop
Control of outputs:
Alarm value
off
limit
lim-prio
2. Fault occurs later: mA-Input
Control of outputs:
Alarm value
on
on
on
The behaviour of the outputs determined by the ranking:
Analogue output
stays on
Alarm value
Relay 1
changes from relay
off
to relay
on
Relay 2
changes from relay
limit
to relay
on
Logic 1
stays on
lim-prio
Second example:
2fault occur parallel
Control of outputs:
Alarm value
on
off
lim-prio
The behaviour of the outputs determined by the ranking:
Analogue output
changes to
Alarm value
Relay 1
is switched
on
Relay 2
is switched
off
Logic 1
stays on
lim-prio
